This invention relates to a cart having extensible auxiliary wheels and, more particularly, to a cart having auxiliary wheels mounted on an extensible platform. The cart of this invention is particularly adapted for transporting articles, although the several features of the invention are not necessarily restricted to that use.
The original Weil cart which is the subject of his U.S. Pat. Nos. 2,841,438; 2,877,047 and 2,877,048 included a frame having auxiliary wheels on its forward end, depending legs pivoted to the frame, the depending legs being adapted to swing rearwardly. The objective of the invention was to permit a one-man operation of the cart wherein that man standing at the rear of the cart could roll the cart up to the rear of a vehicle, such as a hearse, ambulance, or station wagon, and while the forward end of the cart was supported by the engagement of the auxiliary wheels on the loading platform of the vehicle, the operator, supporting the rear portion of the cart, could thrust the cart into the vehicle with the legs of the cart swinging rearwardly to lie generally horizontally beneath the frame of the cart.
In U.S. Pat. No. 3,493,262, owned by the assignee of the present application, there is described a cart which is an improvement in the original Weil cart, the improvement residing particularly in the structure of the rear legs. The rear legs are formed of two sections which are hinged together so that upon collapse of the rear legs the upper sections swing forwardly and the lower portions swing rearwardly. This structure permits a shorter overall length of the frame (or a longer wheel base, as the case may be) while avoiding interference with the man at the rear of the cart as the legs are swung rearwardly. In other words, the distance which the rear legs project rearwardly upon collapse is shortened by twice the length of the upper section of the legs over the structure of the original Weil cart. This foreshortened cart was particularly useful in traveling in elevators, in minimizing the projecting structure during sales demonstrations, and, further, for riding in a shorter vehicle space as, for example, a compact station wagon.